1. The Field of the Invention
The present invention relates to devices and methods for elevating the pelvic position of a surgical patient in a supine position.
2. Background and Relevant Art
Percutaneous bone fixation is a technique used by orthopedic surgeons for the stabilization of unstable fractures. It involves the manipulation, with X-ray guidance, of the fracture into an acceptable position, and the insertion of metal pins through the skin into one bone fragment and across the fracture line into an adjacent bone fragment. Percutaneous fixation falls into the category of minimally invasive surgery, which has become very popular and well described for pelvic and acetabular fractures.
Surgeons commonly perform percutaneous fixation on a radiolucent operating table. A patient undergoing the procedure usually lies in a supine position, i.e. with the front (anterior) facing up and the back (posterior) facing down. Because the operating tables are generally covered with a mattress, the patient tends to “sink” into the mattress a couple of inches. During operation, the patient should be centered on the table; however, the table is generally wider than most all patients. They are designed for the largest patients. As a result, when a patient is centered on the table, the pelvic bone is usually far from the table's edge and in the aforementioned sunken position relative to the plane of the mattress surface.
In many percutaneous fixation procedures, a surgeon must be able to insert drills, pins, screws, or other equipment with a posterior-to-anterior vector. The orientation of the patient, however, can cause the surgeon's hands and equipment to compete or “bump into” the table and mattress, thus compromising the surgeon's ability to place implants at the desired posterior to anterior vector. To overcome this problem, surgeons have conveniently placed a raised bump, such as a roll of sterile towels or a blanket, under the sacrum or tailbone of the patient in an attempt to selectively elevate the patient in order to provide better access to posterolateral aspects of the buttock with the appropriately directed drilling and implant placement.
Lifting a patient with such a sacral “pad”, however, can cause the patient's body to become unstable as the patient tends to rock right and left as if to fall off the pad. Typical sacral pads are conventionally made using sheets, blankets, or towels that are folded, stacked, and often taped so they do not fall apart. This method, however, creates instability of the patient, inconsistency of surface, and, at times, creates interference if done improperly. Furthermore, the shapes of such sacral pads are not optimized to evenly distribute the patient's weight, and the hardness of the pads does not always provide appropriate cushioning to the patient's body. As a result, makeshift sacral pads tend to increase point pressures via body weight loading of bony protuberances, which may aggravate soft tissue damage and breakdown.